Alkylphosphoric acid compounds are known substances with anti-tumor effects.
German published patent 33 43 530.8 (U.S. Pat. No. 5,153,179) discloses preparations for administering pharmaceutically-active compounds including, e.g., phosphatidylcholine. This patent describes the use of aqueous compositions of those active ingredients and others and describes increased penetration of the blood-brain barrier and other tissue barriers, achieved through the use of glycerol alkyl ether as solvents for these active substances.
Investigation of the use of alkyl glycerols with alkyl phosphoric acids such as hexadecylphosphocholine led to the discovery of storage instability. That is, oxidative processes caused peroxides to be formed in the solution which later led to acids and hence a drop in pH due to further decomposition. The pH value is set at 4-6 in the specification.